Pseudomonas & Burkholderia (G-ve Aerobes)

Psuedomonas spp. is considered an ______ and _____ pathogen.

opportunistic and nosocmial

Where does pseudomonas live on the host?

skin (commensal)

GIT

What are the four predisposing factors of Psuedomonas?

• defect in host defense mechanisms

• Impaired host defense

• Loss of competing normal flora

• Persistent moisture

What virulence factors of pseudomonas contribute to tissue damage?

• Exotoxin → cytotoxicity necrosis

• Elastase & Proteases → tissue/corneal damage

• Pyocyanin → oxidative damage

What virulence factors does pseudomonas have that allows it to survive?

• LPS → inflammation

• Pyoverdine → iron acquisition

• Type II & III secretion → deliver virulence factors

• Multidrug resistance & biofilm formatin

Pseudomonas infections have _____ mortality/

Low

Pseudomonas infections are characterized by:

• local and generalized blue or green pus filled abscesses

• Septicemia

• Pneumonia in Minks & Chinchillas

• Keratitis with melting ulcers (horses)

• Otitis in floppy eared dogs

Sheep with pseudomonas have:

green will from pyocyanin and pyoverdine staining

Rabbits, Guinea Pigs, and Rodents with pseudomonas have:

slobbers and moist dermatitis from malocclusion and stomatitis

WHat is the appearance of pseudomonas on a colony?

• Pyocyanin: blue/green

• Pyoverdine: yellow/green fluorescent pus

• Fruity (grape) odor from aminoacetophenone

How do you ID the culture?

MALDI-TOF

True or False: Antimicrobial susceptibility testing is not mandatory for successful therapy.

FALSE

Burkholderia mallei is an ______ parasite of equips.

obligate

True or False: Burkholderia mallei is a biological weapon due to it being highly contagious, fatal, and zoonotic.

TRUE

What species is highly resistant to Burkholderia mallei?

Birds

The nasal form (Glanders) of bulkholderia mallei is characterized by:

• star shaped scars and nodules (stellate scars) in the lower part of turbinate and septum

• Greenish yellow nasal exudate

The pulmonary form (glanders) of bulkholderia mallei is characterized by:

diffuse pneumonia and nodules

The cutaneous form (Farcy) of bulkholderia mallei is characterized by:

• Nodules in the lymphatics and skin

• Dark honey discharge from ulcers

How can you diagnose bulkholderia mallei?

• ELISA and CFT

• Mallein test (intrapalpebral injection of protien fraction of B. Mallei)

If you suspect Glanders, what should you do?

report to state or federal animal health officials

True or False: There is no vaccine or treatment for bulkholderia mallei.

TRUE

Bulkholderia pseudomallei is a ____, free-living, _____ in soil and surface water.

motile; saprophyte

Where is bulkholderia psueomallei endemic?

SE Asia and northern Australia, US GUlf Coast after heavy rain/flooding

B. Psuedomallei causes melioidosis/Glanders.

melioidosis

B. Pseudomallei has a ____ host range.

Broad

What is the incubation period of b. Psuedomallei?

latent infection that can reactivate years later

True or False: B. Pseudomallei is considered a biothreat as well.

TRUE

In dogs with B. Pseudomallei, is it often _____ nfection.

subclinical

How can you diagnose B. Pseudomallei?

• History and geography

• Blood/wound culture

• Imaging

Which species usually has meliodiosis found at slaughter and is commonly confused with tuberculosis?

Pigs

WHat is the appearance of B. Pseudomallei on culture and on stain?

Culture: wrinkled colony form

Stain: bipolar safety pin stain

How can you treat B. Pseudomallei?

long term abx with recurrence when stopped

• endemic: TX NOT AN OPTION - EUTH

True or False: B. Psuedomallei is rarely zoonotic.

TRUE